This decodes the key themes, signs, and symbols found in Christian art: the Eucharist, the image of the Crucifixion, the Virgin Mary, the Saints, Old and New Testament narrative imagery, and iconography. It also explores the theological and historical background of Christian imagery, from the devotional works of the Medieval and Renaissance periods, to the twenty-first century.

Williamson uses examples from, amongst others, Cimabue, Michelangelo, and Rosetti. She concludes by outlining the co-existence in contemporary 'post-Christian' culture of the deliberately controversial works of artists such as Andres Serrano and Chris Ofili, alongside the consciously devotional works of those such as Eric Gill and Peter Blake.